Endocrine Abstracts

Two progesterone receptor (PR) isoforms, the full-length PR-B and the N-terminally truncated PR-A, have distinct reproductive functions, with PR-B being required for a proper mammary gland development. The functional distinction between PR-B and PR-A has partially been attributed to the additional activation function (AF3) domain, localized within the PR-B-unique sequence (PR-BUS). Three highly conserved sequence motifs within AF3 domain are required for the strong transactiva...

Progesterone receptors (PR) are long recognized to suppress estrogen receptor (ER) mediated transcription in breast cancers. However, a mechanistic basis for this repression has been lacking. Recent reports indicate this occurs, in part, through global repositioning of ER on chromatin in the presence of selective PR modulators (SPRMS), both agonists and antagonists [1, 2]. The goal of our studies was to further understand the mechanisms by which PR impacts estrogen-dependent g...